A variety of building materials are used for the exterior of contemporary houses that not only provide structural integrity but also aesthetic appeal. Such building materials include brick, wood, stucco and siding panels. Siding panels are fabricated from a variety of materials such as aluminum, wood and vinyl. Although exterior siding panels are attractive as well as durable, often, the services of professional siding contractors are required due to the difficulty of installing the siding panels onto the house particularly where angled cuts are required. For example, to facilitate installation on an upper portion of a vertical wall proximate to the pitch of a roof the siding panel must be cut at an angle conforming to the pitch of the roof.
To capture angular measurements siding contractors typically use a pocket bevel gauge to determine the appropriate angle necessary for cutting the siding panel to conform to the pitch of the roof. The pocket bevel gauge includes a handle having a slot formed therethrough. A slotted blade is disposed within the slot of the handle and a screw and butterfly nut set enables the siding contractor to lock the blade at any angular position relative to the handle thereby releasably retaining the blade at an angular position on and relative the handle. After guessing at an imaginary horizontal plane, the siding contractor positions the handle parallel thereto and positions the blade at an angle with respect to the pitch of the roof. The bolt and butterfly nut set is tightened to retain the blade in a position relative to the handle so as to capture the angular measurement which can then be transferred onto the siding panel for an appropriate cut.
Another tool used for capturing angular measurement is shown in U.S. Pat. No. 1,324,411 to Rosenholm which discloses a combination tool. This combination tool includes an oblong body having two spirit level tubes so that the oblong body can be disposed in an imaginary horizontal plane without guessing. The oblong body also includes a rule which is pivoted at one end of the oblong body. The oblong body has a longitudinal slot formed into one side edge so that the rule can be folded thereinto. The tool also includes a first locking mechanism for locking the rule in a closed position, a second locking mechanism for locking the rule in its extended position and a third locking mechanism, which is a threaded bolt and nut set, for locking the rule anywhere between its closed position and its extended position. A particular disadvantage in using this combination tool is when a siding contractor must work in muddy conditions when installing the siding panels onto the house. Under such conditions, if this combination tool falls into mud, it could be rendered useless until it is meticulously cleaned because mud could infiltrate the slot and prevent movement of the rule.
U.S. Pat. No. 875,462 to Rowan reveals a combined spirit level and gauge which includes a pair of staffs. Each staff includes a pair of blades with one carrying a horizontally-disposed spirit level tube and the other carrying a vertically-disposed spirit level tube. Each blade is pivotally connected at an end of respective staffs. A threaded bolt and nut set which projects outwardly relative to common sides of the staffs is used to lock the two staffs together at a desired angular position with respect to each other.
Also, two other devices described in U.S. Pat. No. 2,878,569 and U.S. Pat. No. 3,522,657, both to Metrulis can be used to capture angular measurements of structural surfaces relative to an imaginary horizontal plane. Both devices are a combination level, rule and protractor device. The combination level, rule and protractor device includes a pair of arms pivotally connected together by a hinge and a plurality of spaced spirit level tubes. The combination device also includes a protractor mounted on one of the arms and a front cover plate mounted on the other arm. With a locking screw engaged with a locking screw opening, the arms can be locked in any angular position between 0.degree. and 180.degree. with respect to the arms.
The prior art described hereinabove provides a flat side so that the tool can rest flushly against a flat support wall when capturing the angular measurement. Unfortunately, the prior art has only one side which can rest flushly against a wall when capturing the angular measurement. The reverse side has an arm lock mechanism which projects therefrom. Thus, when reversed, i.e., flip-flopping the tool after capturing a right-handed angle so as to capture a left-handed angle, the arm lock mechanism causes the tool to wobble when placed against the wall. Also, all of the prior art tools show a bolt and wing nut set for use as an arm lock mechanism. Typically, a wing nut requires the use of a forefinger and thumb of the siding contractor in order to tighten or loosen the arm lock mechanism.
There is a need in the industry to provide a level angle gauge which can rest flush against a flat support wall without wobbling when capturing a right-handed or a left-handed angular measurement of a structural surface relative to an imaginary horizontal or vertical plane. There is also a need in the industry to provide an arm lock mechanism which is easier to operate. It would be advantageous if the level angle gauge could be easily cleaned if accidentally dropped in mud or dirt. The present invention satisfies these needs and provides this advantage.